One of our customers reported uninterrupted oil leakages on the rods of four cylinders installed on a plastic injection machine. Leakages would regularly occur after about 10000 cycles. Though the customer had replaced rod seals twice, leakages continued to occur, and the problem was far from being resolved. On a closer look, analizying both application and corresponding usage parameters, I realized that the actual line pressure was only 30-35 bars. In such a case, standard seals, unsupported by o-rings, would give birth to the leakages reported by our customer. I suggested increasing oil pressure to 70-80 bars, but since the mold was quite peculiar, it was not possible to do so. So I recommended the installation of special hemmed seals made of thermoplastic materials, which would grant an excellent performance despite the very low pressure. Our customer was satisfied with this solution.